-
Notifications
You must be signed in to change notification settings - Fork 0
/
index.json
1 lines (1 loc) · 24.6 KB
/
index.json
1
[{"authors":["admin"],"categories":null,"content":"Support Scientist for the ELT/METIS instrument at Institute of Astronomy \u0026amp; Astrophysics, Academia Sinica (ASIAA) in Taiwan. Involved in the HiRISE project at LAM, Marseille, to combine high contract imaging and high dispersion spectroscopy at the VLT, and the MASCARA project at Leiden Observatory which searches for transiting exoplanets around the brightest stars. PhD on the prototyping, lab-testing and on-sky demonstration of a new type of broad-band coronagraphs. Amateur-genealogist with an interest in genetics as a tool to research family history.\n","date":1598889600,"expirydate":-62135596800,"kind":"term","lang":"en","lastmod":1598889600,"objectID":"2525497d367e79493fd32b198b28f040","permalink":"https://gotten.github.io/author/gilles-p.p.l.-otten/","publishdate":"0001-01-01T00:00:00Z","relpermalink":"/author/gilles-p.p.l.-otten/","section":"authors","summary":"Support Scientist for the ELT/METIS instrument at Institute of Astronomy \u0026amp; Astrophysics, Academia Sinica (ASIAA) in Taiwan. Involved in the HiRISE project at LAM, Marseille, to combine high contract imaging and high dispersion spectroscopy at the VLT, and the MASCARA project at Leiden Observatory which searches for transiting exoplanets around the brightest stars.","tags":null,"title":"Gilles P.P.L. Otten","type":"authors"},{"authors":["Gilles P.P.L. Otten","A. Vigan","E. Muslimov","M. N'Diaye","E. Choquet","U. Seemann","K. Dohlen","M. Houllé","P. Cristofari","M. W. Phillips","Y. Charles","I. Baraffe","J.-L. Beuzit","A. Costille","R. Dorn","M. El Morsy","M. Kasper","M. Lopez","C. Mordasini","R. Pourcelot","A. Reiners","J.-F. Sauvage"],"categories":null,"content":"","date":1598889600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1598889600,"objectID":"cb3ce0f042de72c2fb3b804cf09780d0","permalink":"https://gotten.github.io/publication/hirise-sim/","publishdate":"2020-09-01T00:00:00+08:00","relpermalink":"/publication/hirise-sim/","section":"publication","summary":"Studies of atmospheres of directly imaged exoplanets with high-resolution spectrographs have shown that their characterization is predominantly limited by noise on the stellar halo at the location of the studied exoplanet. An instrumental combination of high-contrast imaging and high spectral resolution that suppresses this noise and resolves the spectral lines can therefore yield higher quality spectra. We study the performance of the proposed HiRISE fiber coupling between the SPHERE and CRIRES+ at the VLT for spectral characterization of directly imaged planets. Using end-to-end simulations of HiRISE we determine the S/N of the detection of molecular species for known exoplanets in $H$ and $K$ bands, and compare them to CRIRES+. We investigate the ultimate detection limits of HiRISE as a function of stellar magnitude, and we quantify the impact of different coronagraphs and of the system transmission. We find that HiRISE largely outperforms CRIRES+ for companions around bright hosts like $\\beta$ Pic or 51 Eri. For an $H=3.5$ host, we observe a gain of a factor of up to 36 in observing time with HiRISE to reach the same S/N on a companion at 200 mas. More generally, HiRISE provides better performance than CRIRES+ in two-hour integration times between 50-400 mas for hosts with $H","tags":["HiRISE","Astronomy"],"title":"Direct characterization of young giant exoplanets at high spectral resolution by coupling SPHERE and CRIRES+ ","type":"publication"},{"authors":["P. Mollière","T. Stolker","S. Lacour","Gilles P.P.L. Otten","J. Shangguan","B. Charnay","T. Molyarova","M. Nowak","Th. Henning","G.D. Marleau","D.A. Semenov","E. van Dishoeck","F. Eisenhauer","P. Garcia","R. Garcia Lopez","A.Z. Greenbaum","S. Hinkley","P. Kervella","L. Kreidberg","A.L. Maire","E. Nasedkin","L. Pueyo","I.A.G. Snellen","A. Vigan","J. Wang","P.T. de Zeeuw","A. Zurlo"],"categories":null,"content":"","date":1578758400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1578758400,"objectID":"02fd1ca1e2fa1ec6cecc164a97c6b7ea","permalink":"https://gotten.github.io/publication/exogravity/","publishdate":"2020-01-12T00:00:00+08:00","relpermalink":"/publication/exogravity/","section":"publication","summary":"*Context*. Clouds are ubiquitous in exoplanet atmospheres and they represent a challenge for the model interpretation of their spectra. When generating a large number of model spectra, complex cloud models often prove too costly numerically, whereas more efficient models may beoverly simplified.\n*Aims*. We aim to constrain the atmospheric properties of the directly imaged planet HR 8799e with a free retrieval approach.\n*Methods*. We used our radiative transfer code petitRADTRANS for generating the spectra, which we coupled to the PyMultiNest tool. We added the effect of multiple scattering which is important for treating clouds. Two cloud model parameterizations are tested: the first incorporates the mixing and settling of condensates, the second simply parameterizes the functional form of the opacity.\n*Results*. In mock retrievals, using an inadequate cloud model may result in atmospheres that are more isothermal and less cloudy than the input. Applying our framework on observations of HR 8799e made with the GPI, SPHERE, and GRAVITY, we find a cloudy atmosphere governed by disequilibrium chemistry, confirming previous analyses. We retrieve that C/O=$0.60^{+0.07}_{−0.08}$. Other models have not yet produced a well constrained C/O value for this planet. The retrieved C/O values of both cloud models are consistent, while leading to different atmospheric structures: either cloudy or more isothermal and less cloudy. Fitting the observations with the self-consistent Exo-REM model leads to comparable results, without constraining C/O.\n*Conclusions*. With data from the most sensitive instruments, retrieval analyses of directly imaged planets are possible. The inferred C/O ratio of HR 8799e is independent of the cloud model and thus appears to be a robust. This C/O is consistent with stellar, which could indicate that the HR8799e formed outside the CO$_2$ or CO iceline. As it is the innermost planet of the system, this constraint could apply to all HR 8799 planets.","tags":["gravity","Astronomy"],"title":"Retrieving scattering clouds and disequilibrium chemistry in the atmosphere of HR 8799e","type":"publication"},{"authors":["Gilles P.P.L. Otten"],"categories":[],"content":"The exoGravity project is based around a 14 night long large program to cover multiple known directly imaged exoplanets in multiple epochs using the VLTI/GRAVITY instrument (K-band spectrograph). This allows the team to study the astrometry and spectroscopy (at up to $R=4000$) of these planets and their atmospheres.\n","date":1572559200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1572559200,"objectID":"67794f7e68833eace7f58572bafcbee0","permalink":"https://gotten.github.io/project/exogravity/","publishdate":"2019-11-01T00:00:00+02:00","relpermalink":"/project/exogravity/","section":"project","summary":"The exoGravity Large Program uses GRAVITY on the VLTI to study the astrometry and atmospheres of known directly imaged extrasolar planets.","tags":["GRAVITY","Astronomy"],"title":"exoGravity","type":"project"},{"authors":["Gilles P.P.L. Otten"],"categories":[],"content":"The PAPYRUS project was brought to life by the PhD students supported by Postdocs and staff members at LAM in Marseille. It gathers the expertise and equipment that has been built up over the years to design and construct a state-of-art Pyramid Wavefront Sensor. After installation of the visitor instrument at the 1.52 meter telescope at OHP, first light was obtained in June 2022. During these initial on-sky measurements 15% Strehl was achieved on Vega at a wavelength of 635 nanometer.\n","date":1572559200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1572559200,"objectID":"23df9f5b0463ccdd909d6d34d35ffce1","permalink":"https://gotten.github.io/project/papyrus/","publishdate":"2019-11-01T00:00:00+02:00","relpermalink":"/project/papyrus/","section":"project","summary":"Installing an Adaptive Optics instrument based around a Pyramid Wavefront Sensor at the T152 at Observatoire de Haute Provence.","tags":["Papyrus","Astronomy"],"title":"PAPYRUS","type":"project"},{"authors":["A. Vigan","Gilles P.P.L. Otten","E. Muslimov","K. Dohlen","M.W. Phillips","U. Seemann","J.-L. Beuzit","R. Dorn","M. Kasper","D. Mouillet","I. Baraffe","A. Reiners"],"categories":null,"content":"","date":1530028800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1530028800,"objectID":"988b2e6c56174f7343a2fdcfa04e74be","permalink":"https://gotten.github.io/publication/hirise-concept/","publishdate":"2018-06-27T00:00:00+08:00","relpermalink":"/publication/hirise-concept/","section":"publication","summary":"Atmospheric composition provides essential markers of the most fundamental properties of giant exoplanets, such as their formation mechanism or internal structure. New-generation exoplanet imagers, like VLT/SPHERE or Gemini/GPI, have been designed to achieve very high contrast (15 mag) at small angular separations (","tags":["HiRISE","Astronomy"],"title":"Bringing high-spectral resolution to VLT/SPHERE with a fibre coupling to VLT/CRIRES+","type":"publication"},{"authors":["Gilles P.P.L. Otten"],"categories":[],"content":"","date":1517436000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1517436000,"objectID":"d71e8e74a7fe11f184c7d79fcba21f78","permalink":"https://gotten.github.io/project/hirise/","publishdate":"2018-02-01T00:00:00+02:00","relpermalink":"/project/hirise/","section":"project","summary":"Combining high contrast imaging with high dispersion spectroscopy","tags":["HiRISE","Astronomy"],"title":"HiRISE","type":"project"},{"authors":["Gilles P.P.L. Otten","M. Göttgens"],"categories":null,"content":"","date":1514736000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1514736000,"objectID":"a16c438e0d0b423ebfb07e2931c2dcb7","permalink":"https://gotten.github.io/publication/genealogie/","publishdate":"2018-01-01T00:00:00+08:00","relpermalink":"/publication/genealogie/","section":"publication","summary":"In this chapter I cover the genetical research that has supported the archival research to several branches of my ancestors. These studies uncovered unknown relatives in the 19th century and also in the medieval period.","tags":["Genetics","Genealogy"],"title":"Genetical research of our ancestors","type":"publication"},{"authors":["M.H.D. Larmuseau","Gilles P.P.L. Otten","R. Decorte","P. Van Damme","M. Moisse"],"categories":null,"content":"","date":1509465600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1509465600,"objectID":"d5609b49457914306a78244bb97fdb09","permalink":"https://gotten.github.io/publication/larmuseau/","publishdate":"2017-11-01T00:00:00+08:00","relpermalink":"/publication/larmuseau/","section":"publication","summary":"Y-chromosomal single nucleotide polymorphisms (Y-SNPs) represent a powerful tool in forensic research and casework, especially for inferring paternal ancestry of unknown perpetrators and unidentified bodies. However, the wealth of recently discovered Y-SNPs, the ‘jungle’ of different evolutionary lineage trees and nomenclatures, and the lack of population-wide data of many phylogenetically mapped Y-SNPs, limits the use of Y-SNPs in routine forensic approaches. Recently, a concise reference phylogeny of the human Y chromosome, the ‘Minimal Reference Y-tree’, was introduced aiming to provide a stable phylogeny with optimal global discrimination capacity by including the most resolving Y-SNPs. Here, we obtained a representative sample of 270 whole-genome sequences (WGS) to grasp the Y-SNP variation within the autochthonous Flemish population (Belgium, Western Europe) according to this reference Y-tree. The high quality of the Y-SNP calling was guaranteed for the WGS sample as well as its representativeness for the Flemish population based on the comparison of the main haplogroup frequencies with those from earlier studies on Flanders and the Netherlands. The 270 Flemish Y chromosomes were assigned to 98 different sub-haplogroups of the Minimal Reference Y-tree, showing its high potential of discrimination and confirming the spectrum of evolutionary lineages within Western Europe in general and within Flanders in particular. The full database with all Y-SNP calls of the Flemish sample is public available for future updates including forensic and population genetic studies. New initiatives to categorise Y-SNP variation in other populations according to the reference phylogeny of the Y chromosome are highly encouraged for forensic applications. Recommendations to realise such future population sample sets are discussed based on this study.","tags":["Genetics","Genealogy"],"title":"Defining Y-SNP variation among the Flemish population (Western Europe) by full genome sequencing","type":"publication"},{"authors":["Gilles P.P.L. Otten"],"categories":[],"content":"The MASCARA project was designed and constructed to discover transiting exoplanets around the brightest stars in the sky. All stars brighter than magnitude 8.4 above Airmass 2 are imaged every 6.4 seconds with 6.4 second integration time, creating continuous exposures. Two stations have been constructed, one in La Palma, Spain and the other in La Silla, Chile. Two smaller sister station with only two cameras called bRing reside in Sutherland South Africa and Siding Springs, Australia.\n","date":1498860000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1498860000,"objectID":"7c4b97209a9dd46bba4d8f448a402634","permalink":"https://gotten.github.io/project/mascara/","publishdate":"2017-07-01T00:00:00+02:00","relpermalink":"/project/mascara/","section":"project","summary":"The Multi-Site All-Sky CAmeRA searches for transiting exoplanets around the brightest stars in the sky.","tags":["MASCARA","Astronomy"],"title":"MASCARA","type":"project"},{"authors":["G.J. Talens","J.F.P. Spronck","A.-L. Lesage","Gilles P.P.L. Otten","R. Stuik","D. Pollacco","I.A.G. Snellen"],"categories":null,"content":"","date":1493568000,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1493568000,"objectID":"79c2c9318df49c4c2bb5994e4384102e","permalink":"https://gotten.github.io/publication/mascara/","publishdate":"2017-05-01T00:00:00+08:00","relpermalink":"/publication/mascara/","section":"publication","summary":"This paper describes the design, operations, and performance of the Multi-site All-Sky CAmeRA (MASCARA). Its primary goal is to find new exoplanets transiting bright stars, $4 ","tags":["MASCARA","Astronomy"],"title":"The Multi-site All-Sky CAmeRA (MASCARA)-Finding transiting exoplanets around bright (mV \u003c 8) stars","type":"publication"},{"authors":["Gilles P.P.L. Otten","F. Snik","M.A. Kenworthy","C.U. Keller","J.R. Males","K.M. Morzinski","L.M. Close","J.L. Codona","P.M. Hinz","K.J. Hornburg","L.L. Brickson","M.J. Escuti"],"categories":null,"content":"","date":1484150400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1484150400,"objectID":"ba8f009497472ae3f7b78bd0136f43af","permalink":"https://gotten.github.io/publication/magao/","publishdate":"2017-01-12T00:00:00+08:00","relpermalink":"/publication/magao/","section":"publication","summary":"We report on the performance of a vector apodizing phase plate coronagraph that operates over a wavelength range of 2–5 μm and is installed in MagAO/Clio2 at the 6.5 m Magellan Clay telescope at Las Campanas Observatory, Chile. The coronagraph manipulates the phase in the pupil to produce three beams yielding two coronagraphic point-spread functions (PSFs) and one faint leakage PSF. The phase pattern is imposed through the inherently achromatic geometric phase, enabled by liquid crystal technology and polarization techniques. The coronagraphic optic is manufactured using a direct-write technique for precise control of the liquid crystal pattern and multitwist retarders for achromatization. By integrating a linear phase ramp to the coronagraphic phase pattern, two separated coronagraphic PSFs are created with a single pupil-plane optic, which makes it robust and easy to install in existing telescopes. The two coronagraphic PSFs contain a 180° dark hole on each side of a star, and these complementary copies of the star are used to correct the seeing halo close to the star. To characterize the coronagraph, we collected a data set of a bright (mL = 0–1) nearby star with ~1.5 hr of observing time. By rotating and optimally scaling one PSF and subtracting it from the other PSF, we see a contrast improvement by 1.46 magnitudes at $3.5\\ \\lambda /D$. With regular angular differential imaging at 3.9 μm, the MagAO vector apodizing phase plate coronagraph delivers a $5\\sigma \\ {\\rm{\\Delta }}\\mathrm{mag}$ contrast of 8.3 ($={10}^{-3.3}$) at 2 $\\lambda /D$ and 12.2 ($={10}^{-4.8}$) at $3.5\\ \\lambda /D$.","tags":["vAPP","Astronomy"],"title":"On-sky performance analysis of the vector apodizing phase plate coronagraph on MagAO/Clio2","type":"publication"},{"authors":["Gilles P.P.L. Otten","F. Snik","M.A. Kenworthy","M.N. Miskiewicz","M.J. Escuti"],"categories":null,"content":"","date":1484150400,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1484150400,"objectID":"538619a1c5b05c52ec96216cdce078a5","permalink":"https://gotten.github.io/publication/performance-vapp/","publishdate":"2017-01-12T00:00:00+08:00","relpermalink":"/publication/performance-vapp/","section":"publication","summary":"One of the main challenges for the direct imaging of planets around nearby stars is the suppression of the diffracted halo from the primary star. Coronagraphs are angular filters that suppress this diffracted halo. The Apodizing Phase Plate coronagraph modifies the pupil-plane phase with an anti-symmetric pattern to suppress diffraction over a 180 degree region from 2 to 7 λ/D and achieves a mean raw contrast of $10^{−4}$ in this area, independent of the tip-tilt stability of the system. Current APP coronagraphs implemented using classical phase techniques are limited in bandwidth and suppression region geometry (i.e. only on one side of the star). In this paper, we introduce the vector-APP (vAPP) whose phase pattern is implemented through the vector phase imposed by the orientation of patterned liquid crystals. Beam-splitting according to circular polarization states produces two, complementary PSFs with dark holes on either side. We have developed a prototype vAPP that consists of a stack of three twisting liquid crystal layers to yield a bandwidth of 500 to 900 nm. We characterize the properties of this device using reconstructions of the pupil-plane pattern, and of the ensuing PSF structures. By imaging the pupil between crossed and parallel polarizers we reconstruct the fast axis pattern, transmission, and retardance of the vAPP, and use this as input for a PSF model. This model includes aberrations of the laboratory set-up, and matches the measured PSF, which shows a raw contrast of $10^{−3.8}$ between 2 and 7 λ/D in a 135 degree wedge. The vAPP coronagraph is relatively easy to manufacture and can be implemented together with a broadband quarter-wave plate and Wollaston prism in a pupil wheel in high-contrast imaging instruments. The liquid crystal patterning technique permits the application of extreme phase patterns with deeper contrasts inside the dark holes, and the multilayer liquid crystal achromatization technique enables unprecedented spectral bandwidths for phase-manipulation coronagraphy.","tags":["vAPP","Astronomy"],"title":"Performance characterization of a broadband vector Apodizing Phase Plate coronagraph ","type":"publication"},{"authors":["Gilles P.P.L. Otten"],"categories":[],"content":"The vector Apodizing Phase Plate is a coronagraph that uses a multi-layered patterned liquid crystal device to produce an achromatic phase response that spans up to one order of magnitude. The picture above shows a prototype that was specced to operate from 500-900 nm.\n","date":1446328800,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1446328800,"objectID":"28c106ae6cda006cf6b33aff0a9e2e0c","permalink":"https://gotten.github.io/project/vectorapp/","publishdate":"2015-11-01T00:00:00+02:00","relpermalink":"/project/vectorapp/","section":"project","summary":"The vector Apodizing Phase Plate coronagraph (vAPP) surpresses starlight on both sides of a star using an achromatic pupil-plane coronagraph based on liquid-crystal technology. This enables an improved detection and characterization of exoplanets and their atmospheres.","tags":["vAPP","Astronomy"],"title":"Vector APP","type":"project"},{"authors":["Gilles P.P.L. Otten"],"categories":[],"content":"I have used genetic research to study several branches of my ancestors and break down some brick walls. The most striking results have been anonymized for privacy reasons and published in a Book Section in the \u0026ldquo;Drents Genealogisch Jaarboek 2017\u0026rdquo;.\n","date":1388527200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1388527200,"objectID":"ed1d2605d6fbffa0e34df80e3000733c","permalink":"https://gotten.github.io/project/genetics/","publishdate":"2014-01-01T00:00:00+02:00","relpermalink":"/project/genetics/","section":"project","summary":"DNA is a powerful tool in family research and has provided valuable clues in research of my family's origins.","tags":["Genealogy","Genetics"],"title":"Genetic genealogy","type":"project"},{"authors":["F. Snik","Gilles P.P.L. Otten","M.A. Kenworthy","M.N. Miskiewicz","M. Escuti","C. Packham","J. Codona"],"categories":null,"content":"","date":1347465600,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":1347465600,"objectID":"ce17f79ea08287b2495cda62b5f574c9","permalink":"https://gotten.github.io/publication/vapp-concept/","publishdate":"2012-09-13T00:00:00+08:00","relpermalink":"/publication/vapp-concept/","section":"publication","summary":"The apodizing phase plate (APP) is a solid-state pupil optic that clears out a D-shaped area next to the core of the ensuing PSF. To make the APP more efficient for high-contrast imaging, its bandwidth should be as large as possible, and the location of the D-shaped area should be easily swapped to the other side of the PSF. We present the design of a broadband APP that yields two PSFs that have the opposite sides cleared out. Both properties are enabled by a half-wave liquid crystal layer, for which the local fast axis orientation over the pupil is forced to follow the required phase structure. For each of the two circular polarization states, the required phase apodization is thus obtained, and, moreover, the PSFs after a quarter-wave plate and a polarizing beam-splitter are complementary due to the antisymmetric nature of the phase apodization. The device can be achromatized in the same way as half-wave plates of the Pancharatnam type or by layering self-aligning twisted liquid crystals to form a monolithic film called a multi-twist retarder. As the VAPP introduces a known phase diversity between the two PSFs, they may be used directly for wavefront sensing. By applying an additional quarter-wave plate in front, the device also acts as a regular polarizing beam-splitter, which therefore furnishes high-contrast polarimetric imaging. If the PSF core is not saturated, the polarimetric dual-beam correction can also be applied to polarized circumstellar structure. The prototype results show the viability of the vector-APP concept.","tags":["vAPP","Astronomy"],"title":"The vector-APP: a broadband apodizing phase plate that yields complementary PSFs","type":"publication"},{"authors":["Gilles P.P.L. Otten"],"categories":[],"content":"Genealogy In late 2000 in my second year of high school I was introduced during lessons in History to genealogical research. Almost continuously since that moment I have worked on gathering information on my ancestors as a hobby.\nAfter 20 years I want to release some of the information to the wider public. For family members a database can be found with the link at the top of the page.\nAutomatic transcription of hand-written text Since several years the Transkribus software is available that uses various trained neural networks to read hand-written text. It has a steep learning curve but once you are accustomed to it it can accelerate transcriptions. As an experiment I applied it to the indices of the death records of Bardenberg from the year 1876 up to 1888 and corrected the 95% accurate transcription.\nThe file located here has the first ten years as an example.\n","date":967759200,"expirydate":-62135596800,"kind":"page","lang":"en","lastmod":967759200,"objectID":"52d80e988a902f06c97ed69d24e89c10","permalink":"https://gotten.github.io/project/genealogy/","publishdate":"2000-09-01T00:00:00+02:00","relpermalink":"/project/genealogy/","section":"project","summary":"Otten family tree with more than 10000 relatives. Updated since the year 2000.","tags":["Genealogy"],"title":"Genealogy","type":"project"}]